What is codeine?

Codeine is an opioid medicine that is only available with a prescription from your doctor.

How does codeine work?

Codeine works directly on the central nervous system and reduces feelings of pain by interrupting the way nerves signal pain between the brain and the body.

It also suppresses the activity centre in the brain that controls coughing.

What is codeine used for?

Codeine is used for short-term pain relief. It should only be used when other forms of non-opioid pain relief have not been successful in managing pain. When opioid medicine is required for pain relief, options other than codeine are often preferred because they offer more predictable effects and are generally safer for most people.

Some people will not experience pain relief from codeine because their bodies are unable to process the medicine. This is due to a genetic difference, which is more common in Caucasians.

Other people have a genetic difference that makes them process codeine faster — this can lead to higher doses of codeine being released quickly into the body, and an increased chance of overdose or side effects. This genetic difference is more common in North African and Middle Eastern communities.

Codeine is not usually recommended for the treatment of chronic pain.

Codeine may also relieve a dry cough, although it is not generally recommended for this purpose.

In some situations, codeine can also relieve diarrhoea by reducing the motility (movement) of the intestines.

What forms of codeine are available?

Codeine is available in tablet form and as an oral liquid. Codeine is also available in a tablet formulation combined with other medicines, such as paracetamol, ibuprofen or aspirin.

What are the possible side effects of taking codeine?

All opioids, including codeine, can have side effects including life-threatening breathing problems. The chance of these side effects is higher:

• when first taking codeine
• after a dosage increase
• if you are older
• if you have an existing lung problem

The side effects of codeine are similar to those of other opioids, and include:

• constipation
• headache or dizziness
• fatigue or drowsiness (especially soon after a dose)
• loss of appetite, nausea and vomiting

What are the risks associated with taking codeine?

Opioids are strong pain medicines and can cause life-threatening breathing problems.

Codeine may make it difficult for you to drive or operate heavy machinery. If you have recently started taking an opioid medicine, or changed the dosage, you may be more likely to have an accident. Ask your doctor if it is safe and legal to drive while taking codeine. Also contact your car insurer, as you may not be covered for accidents that occur while you are taking codeine.

If your kidney or liver function is impaired, your doctor may decide that codeine is not appropriate for you. There are other factors that may limit your use of codeine — for example, if you drink alcohol or take other medicines such as benzodiazepines that can cause drowsiness.

Your doctor is the best person to advise you on whether codeine is the right medicine for you, how much you need and how long to take it for.

Opioid tolerance and dependence

If you use opioid medicines, you may also develop tolerance. This means that you may need to take larger amounts of the opioid to get the same effect. The chance of side effects also increases with a higher dose.

It's possible to become dependent on this medicine even if you take it exactly as prescribed by your doctor. Your doctor will help monitor how you use codeine, to reduce your chance of harm, including through misuse, abuse and addiction.

If you are concerned that you are becoming addicted to or dependent on codeine let your doctor know so that you can get help. You can also call the National Alcohol and Other Drug Hotline (1800 250 015) for 24/7 support and treatment information.

Opioid overdose

If you take too much codeine (known as an overdose), it's important to get immediate medical attention. Overdose of opioid medicines can cause you to stop breathing.

Symptoms of overdose include:

• feeling sleepy
• difficulty breathing
• loss of consciousness
• pinpoint (very small) pupils

Access to overdose-reversing medication

Naloxone is a medicine that can temporarily reverse the effects of an opioid overdose. The Australian Government is offering this medicine free of charge and without a prescription to people who may experience, or witness, an opioid overdose.

Learn more about the Take Home Naloxone program.

How do I take codeine?

Always take it exactly as your doctor has prescribed.

Your doctor may recommend a diet high in fibre or using laxatives while you take codeine to prevent opioid-induced constipation.

Continue to take codeine for as long as your doctor tells you to. If you stop taking codeine suddenly, you may experience withdrawal symptoms.

How do I dispose of medicines safely?

It's important you dispose of unwanted opioid medicines safely. Unused medicines can be returned to any pharmacy. Don't keep unused codeine 'just in case'. This can lead to dangerous or inappropriate use.

Keep codeine out of reach of children and pets. Never throw medicines into a garbage bin or flush them down the toilet, as this is dangerous to others and harmful to the environment.

When should I see my doctor?

If your pain is not well controlled with codeine or you have any new, unexpected or unwanted side effects, see your doctor.

Are there alternatives to codeine?

Everyone's pain is unique, and different pain relief medicines will work in different circumstances. Some people's pain will respond well to non-opioid medicines, which are generally associated with fewer problems and side effects.

Always check with your doctor or pharmacist before making any change to the dosage or type of medicine you take.

If you have chronic (long-term) pain, your doctor might suggest lifestyle changes to help manage the discomfort. This may include:

• improving your physical fitness
• activity pacing
• social activities
• relaxation techniques
• overall health management

Read more on options for managing chronic pain.

If you are taking codeine to suppress your cough, there are other medicines available at a pharmacy. Talk to your doctor or pharmacist about suitable options.

Resources and support

Asking about your treatment or medicine is important to help you understand your options.

Here's a guide to questions you should ask your pharmacist or doctor before taking any medicine.

See also this list of medicines that contain codeine and read the consumer information medicine (CMI) leaflet for the brand prescribed, or:

• Call 1300 MEDICINE (1300 633 424) to talk about the medicines you are taking for your pain.
• Discuss your pain on the Pain Link telephone helpline (1300 340 357) which is staffed by volunteers with personal experience of chronic pain.
• Go to Painaustralia to find pain services and programs in your area.
• Learn more about prescription opioids on Choosing Wisely.
• If you are struggling with addiction to alcohol or other drugs, call the National Alcohol and Other Drug Hotline (1800 250 015) for 24/7 support and treatment information.

Languages other than languages

The Alcohol and Drug Foundation has translated their guide to using medicines safely into many community languages.

Information for Aboriginal and/or Torres Strait Islander peoples

• Visit Positive Choices for an overview of drug services and resources for Aboriginal and Torres Strait Islander people and communities.
• Your Room is a website with resources and information about drugs and has information for Aboriginal and/or Torres Strait Islander people.
• Learn more about pain management on Pain Management Network.